Computerized DC bridge of thermistor measurement or localised power loss in magnetic materials
W. Derebasi, T. Meydan, M. Goktape, M.H. So · 1992. Digests of Intermag. International Magnetics Conference · 1992
It has been reported that a dc bridge circuit with a thermistor as a temperature sensor can be used to measure localised power loss (LPL) by observing the rate of rise of temperature in magnetic cores. In recent years advances in precision electronic components have made simpler circuits feasible for accurate temperature measurement applications. The presented study describes a new design of a thermistor circuit with a dc bridge where simplicity, repeatability, reproducibility and accuracy were the main features. The bridge auxiliary circuit consisted of; two instrumentation amplifiers, a AD524 chip was used with preset gains of x1, x10, x100 and x1000, and two fourth-order Butterworth low pass filters which display a cut-off frequency less than 0.5Hz as shown in Fig. 1.